How to order CollectionLink items?

I have a collection of items (that can be reordered), and a singleton with a field of type “CollectionLink” toward this collection.

I don’t really understand what is the default ordering pattern of the CollectionLink items.

How can I reorder the items of the collectionLink?

Thanks!

I just found the solution.

Once the CollectionLinks items have been saved (not just after having been linked), it is possible to drag the item in the list.